U.S. Pat. No. 2,234,914 issued Mar. 11, 1941 discloses an apparatus in which a plurality of parallel yarn strands are applied with dye from a conduit which is disposed above and in transverse relation to the yarn strands and from which downwardly extending nozzles depend and through which dye is supplied to the strands of yarn, the transverse conduit and its downwardly depending nozzles being transversely reciprocable relative to the yarn strands.
Since the apparatus of this prior patent is arranged to apply dye at only one point along the length of yarn strands during each transverse movement, it is quite slow in performing a yarn dyeing operation.
U.S. Pat. No. 4,100,724 issued July 18, 1978 discloses apparatus in which a yarn strand is passed under dye injection nozzles and then through a blower nozzle which twists the yarn and disposes of surplus dye liquid.
U.S. Pat. No. 4,361,019 issued Nov. 30, 1982 discloses a yarn dyeing apparatus wherein one or more strands of yarn is passed through a falling stream of liquid dye which is at boiling temperature. The falling stream may be interrupted intermittently or may be traversed to and fro of the yarn so as to dye the yarn intermittently. Provision is made for passing the yarn through a dye vat so as to dye portions of the yarn which were not dyed by the reciprocal applicator.